使用ElementTree解析Python XML：如何查找具有相同名称的元素的值？

Question

免责声明：我是一般的Python，XML和编程新手。代码（我从互联网上偷取）的作品，但有一些问题，我似乎无法找到答案或围绕我的大脑...

我想解析XML文件从grants.gov xml extract website与删除所有不在“不受限制”资格类别（在XML中标记为“EligibilityCategory”为“99”）的赠款并输出新的xml文件。

我有下面的代码正确删除不感兴趣的资金哎呀，还删除了有多个EligibilityCategorys其中还包括一个“99”的资金有机磷农药。我认为这是因为.find只抓住了第一次发生的事情。我试图使用.findall，但无法解决。预先感谢您的帮助。

import xml.etree.ElementTree as etree 
tree = etree.parse('sample.xml') 
root = tree.getroot() 

for FundingOppSynopsis in root.findall('FundingOppSynopsis'): 
    ID = int(FundingOppSynopsis.find('EligibilityCategory').text) 
    if ID != 99: 
     root.remove(FundingOppSynopsis) 

tree.write("Output/output.xml", xml_declaration=True, encoding='UTF-8', method="xml") 

样品（显著下跌剃）XML：

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE Grants SYSTEM "http://apply07.grants.gov/search/dtd/XMLExtract.dtd"> 
<Grants> 
    <FundingOppSynopsis> 
     <FundingOppNumber>USDA-RMA-RME-2008-03</FundingOppNumber> 
     <ApplicationsDueDate>03242008</ApplicationsDueDate> 
     <Office>Risk Management Agency</Office> 
     <Agency>Department of Agriculture</Agency> 
     <EligibilityCategory>25</EligibilityCategory> 
    </FundingOppSynopsis> 
    <FundingOppSynopsis> 
     <FundingOppNumber>NPS-ARRAWHIS100315</FundingOppNumber> 
     <ApplicationsDueDate>11282009</ApplicationsDueDate> 
     <Office>National Park Service</Office> 
     <Agency>Department of the Interior</Agency> 
     <EligibilityCategory>00</EligibilityCategory> 
    </FundingOppSynopsis> 
    <FundingOppSynopsis> 
     <FundingOppNumber>OFDA-FY08-002-APS</FundingOppNumber> 
     <ApplicationsDueDate>10102008</ApplicationsDueDate> 
     <Office>None</Office> 
     <Agency>Agency for International Development</Agency> 
     <EligibilityCategory>99</EligibilityCategory> 
    </FundingOppSynopsis> 
    <FundingOppSynopsis> 
     <FundingOppNumber>AK-NOI08-0004</FundingOppNumber> 
     <ApplicationsDueDate>07142008</ApplicationsDueDate> 
     <Office>Bureau of Land Management</Office> 
     <Agency>Department of the Interior</Agency> 
     <EligibilityCategory>99</EligibilityCategory> 
    </FundingOppSynopsis> 
    <FundingOppSynopsis> 
     <FundingOppNumber>RD-RBP-BIOMASS-2007-FULL</FundingOppNumber> 
     <ApplicationsDueDate>11162007</ApplicationsDueDate> 
     <Office>Business and Cooperative Programs</Office> 
     <Agency>Department of Agriculture</Agency> 
     <EligibilityCategory>06</EligibilityCategory> 
     <EligibilityCategory>12</EligibilityCategory> 
     <EligibilityCategory>13</EligibilityCategory> 
     <EligibilityCategory>20</EligibilityCategory> 
     <EligibilityCategory>22</EligibilityCategory> 
     <EligibilityCategory>23</EligibilityCategory> 
     <EligibilityCategory>25</EligibilityCategory> 
    </FundingOppSynopsis> 
    <FundingOppSynopsis> 
     <FundingOppNumber>BAA07-10</FundingOppNumber> 
     <ApplicationsDueDateExplanation>The due dates and times established for the receipt of White Papers and Full Proposals are as indicated in Section IV, Paragraph 3 of the BAA. </ApplicationsDueDateExplanation> 
     <Office>Office of Procurement Operations - Grants Division</Office> 
     <Agency>Department of Homeland Security</Agency> 
     <EligibilityCategory>00</EligibilityCategory> 
     <EligibilityCategory>01</EligibilityCategory> 
     <EligibilityCategory>02</EligibilityCategory> 
     <EligibilityCategory>04</EligibilityCategory> 
     <EligibilityCategory>05</EligibilityCategory> 
     <EligibilityCategory>06</EligibilityCategory> 
     <EligibilityCategory>07</EligibilityCategory> 
     <EligibilityCategory>08</EligibilityCategory> 
     <EligibilityCategory>11</EligibilityCategory> 
     <EligibilityCategory>12</EligibilityCategory> 
     <EligibilityCategory>13</EligibilityCategory> 
     <EligibilityCategory>20</EligibilityCategory> 
     <EligibilityCategory>21</EligibilityCategory> 
     <EligibilityCategory>22</EligibilityCategory> 
     <EligibilityCategory>23</EligibilityCategory> 
     <EligibilityCategory>25</EligibilityCategory> 
     <EligibilityCategory>99</EligibilityCategory> 
    </FundingOppSynopsis> 
</Grants> 

Answer 1

你需要提取使用的findall类别列表，然后检查99是在该列表中。您可以使用这样的list comprehension：

for FundingOppSynopsis in root.findall('FundingOppSynopsis'): 
    IDs = [int(category.text) for category in FundingOppSynopsis.findall('EligibilityCategory')] 
    if 99 not in IDs: 
     root.remove(FundingOppSynopsis) 

Answer 2

你可以使用一个XPATH要求达到你想要做什么。

import xml.etree.ElementTree as etree 
tree = etree.parse('sample.xml') 
root = tree.getroot() 

req = tree.findall("./FundingOppSynopsis[EligibilityCategory='99']") 

for r in req: 
    print r 

我做回谁拥有孩子的文档的所有FundingOppSynopsis元素的列表请求标签包含文本“99” EligibilityCategory。有关XPath请求here

更多信息。大约在Python here XPATH使用

更多信息。